In order to position a biopsy needle under image guidance more accurately in the suspicious tissue, tissue sensing at the tip of the device is required. Current biopsy needle do not have such tissue feedback possibilities. Recently, elongated interventional devices like that shown in FIG. 1 have been reported with optical fibers 110 integrated into the device 100 allowing tissue feedback at the tip of the device. In order to allow tissue discrimination these devices employed diffuse reflectance spectroscopy. In order to sense chromophores in the tissue having low concentrations the fiber distance 120 between the source and detector fiber are designed to be as large as possible. In general a needle like device 100 has only limited diameter. In order to make the source-detector fiber distance large the fiber ends are positioned at the slanted surface of the tip of needle allowing fiber distances larger than the diameter of the needle.
FIGS. 2 and 3 show different views of another conventional biopsy device 200 with a notch 230 at the circumference of the shaft and a tubular member 240 for selectively covering the notch. However, a large source-detector fiber distance cannot be realized when integrating fibers 110 into the device 200. The reason for this is the notch that is required in order to be able to take biopsies. As a result of this when integrating the fibers 110 into the biopsy device and since the fibers must not be in the notch of the biopsy needle the fiber distance 120 that can be achieved is only small.